Does reducing unhealthier options or increasing healthier options increase healthier selections from vending machines?

In a novel study we compared the impact of increasing and decreasing the number of slots containing healthier and less-healthy options in vending machines in one English hospital. We were interested in the impact on snacks and cold drinks selected.

Reducing the proportion of less healthy cold drinks from 25% to 5% of slots halved the energy purchased from drinks, suggesting this is a promising strategy for encouraging healthier drink selections. Findings were inconclusive when less-healthy snacks were reduced and healthier drinks or snacks were increased.

Further research is needed to establish whether any effects might be smaller for snacks, and/or when the proportion of sales involving healthier options is lower initially.

Read the findings of the study in full here

Pechey, R, Jenkins, H, Cartwright, E, Marteau, TM (2019). Altering the availability of healthier vs. less healthy items in UK hospital vending machines: a multiple treatment reversal design. IJBNPA: 16(114)